private bool ValidateUser()
 {
     if (Ultilities.StringIsEmptyOrNull(User.Name))
     {
         SendDisplayAlert("Error", "Name is not allowed empty!");
         return(false);
     }
     if (Ultilities.StringIsEmptyOrNull(User.Email))
     {
         SendDisplayAlert("Error", "Email is not allowed empty!");
         return(false);
     }
     else if (!Ultilities.StringIsEmail(User.Email))
     {
         SendDisplayAlert("Error", "That is not email address!");
         return(false);
     }
     if (Ultilities.StringIsEmptyOrNull(User.Password))
     {
         SendDisplayAlert("Error", "Password is not allowed empty!");
         return(false);
     }
     if (Ultilities.StringIsEmptyOrNull(User.Address))
     {
         SendDisplayAlert("Error", "Address is not allowed empty!");
         return(false);
     }
     if (Ultilities.StringIsEmptyOrNull(User.ContactNumber))
     {
         SendDisplayAlert("Error", "Contact Number is not allowed empty!");
         return(false);
     }
     if (!Ultilities.StringIsPhoneNumber(User.ContactNumber))
     {
         SendDisplayAlert("Error", "That is not a contact number");
         return(false);
     }
     return(true);
 }